Generally, as shown in FIG. 1, plasma display devices are comprised of striped anodes 30 and cathodes 40 arranged in matrix form on the inner surfaces of a face plate 10 and a rear plate 20 respectively, and barrier ribs 50 disposed, to prevent crosstalk, between anodes 30 and bridging the face plate and rear plate. The plasma display devices are constructed such that light of a high luminance is emitted at intersections of the anodes and cathodes or pixels by instantaneously applying high voltage to the anode and cathode exposed to the space filled with discharge gas such as mercury or argon. The plasma display devices range from displays particularly adapted for letters and drawings to larger displays adapted for moving pictures. Such plasma display devices are studied for use in HDTV displays but their design and fabrication are difficult because of the many pixels disposed within the unit area. In particular, anodes and cathodes should be arranged very closely which demand makes the design and material selection for the device very complicated. The selected material for the cathode should be one which can resist bombardment of ions and has low reaction with discharge gas and low resistance. For instance, in a plasma display device using mercury gas, the use of silver paste of high conductivity for forming the cathode produces amalgam. For this reason, nickel paste having low conductivity but high endurance against bombardment of ions and low reaction has been used instead of silver paste. However, in this case, since material resistance is high, in plasma display devices of high resolution requiring very thin and long cathodes, the cathode line resistance increases from one reference point as it becomes farther from that reference point. As a result cathode current is lowered at each pixel or intersection of anode and cathode from the reference point, which widens the difference in luminance between pixels. Particularly, the nickel paste makes the differences wider because the nickel paste has changeable resistance value, depending on the given conditions. As a result, the conventional material cannot be used for cathodes for plasma display devices of high resolution and large size. Thus, the development of a new material and improvement in the construction of the devices are required.